Vehicles including automobile sport utility vehicles, station wagons, mini-vans, cross-over vehicles, cargo vans and trucks often provide an access door, commonly known as a lift-gate door. Other similar door designs include hatchback doors, sliding doors and horizontally swinging doors. Although these door designs can be mounted differently, for simplicity, these door designs will hereinafter be summarized in reference to lift-gate doors. Lift-gate doors are frequently hinged along an upper horizontal surface, and latch adjacent to a flooring system of the automobile, commonly adjacent to the rear fender of the automobile. One or more latches can be used. The side edges of lift-gate doors are generally not hinged or physically connected to the vehicle structure or support posts at the rear of the vehicle. Motion of the vehicle therefore can result in “match-boxing”, or non-parallel deflection of the support posts relative to the squared sides of the lift-gate door.
Match-boxing is undesirable for several reasons. First, side-to-side or non-parallel motion of support posts can impart additional vehicle noise, known as “chucking” at the lift-gate latch as the vehicle travels along rough or uneven surfaces. Second, vehicle drive train vibration known as idle or “drive train boom” can be transmitted as noise into the passenger compartment via known sliding wedge designs. Third, unless a mechanism is positioned between the lift-gate door edge and the support posts of the vehicle, full structural allowance for the stiffness of the lift-gate cannot be used in the design of the support structure area.
In order to include the stiffness of the lift-gate door in the analysis and design of structural support posts, wedge assemblies having movable slides have been used which displace to span the gap between the lift-gate door and the support post. These assemblies reduce match-box deflection of the support posts by transferring some deflection load to the lift-gate door using wedge assemblies generally positioned between each support post and the lift-gate door. The wedge assembly can be fastened to either or both edges of the lift-gate door or to an edge of one or both of the support posts. In a further known design, a slide assembly is positioned against each lift-gate door side edge and a striker plate is separately mounted to each support post such that the slide engages the striker plate to limit match-boxing of the support posts.
Common designs for sliding wedge assemblies have several problems. First, vehicle rattling noise is produced if the slide is not maintained in continuous contact with the striker plate (or vehicle support post) throughout the travel length of the slide. Tolerances used for common wedge assembly slides permit easy translation, but can result in rattling between the parts during vehicle travel. Second, vehicle build variation, vehicle manufacturing tolerances and/or frame vertical deflection during vehicle use can contribute to a disconnect or non-contact between the slide and the striker plate (or vehicle support post). If the slide is not maintained in contact with the vehicle support post or striker plate, rattling can occur. Third, contaminants such as dirt which contact portions of the wedge assembly could prevent the slide from moving freely, thus potentially resulting in increased chucking and/or increased lift-gate closing effort. Fourth, the hard plastic material commonly used for sliding wedge designs may not dampen the vibration caused by the drive train during idle operation, thus further contributing to drive train boom.